Water samples are collected under a strict protocol designed to prevent contamination during collection and delivery. Students measure temperature in the field and pH when they return to the lab at Thompson Valley High School. Portions of each sample remain preserved in coolers and are delivered to the City of Ft. Collins water quality lab, which conducts nine different analyses for each site.

By looking at this SWAT data, we can explore some trends in Big Thompson River water quality. Trend analysis can be a tricky prospect though. Factors such as weather, varying stream flows and local events can influence the water quality of a given sample. Test results also are affected by changes in collection and/or analysis methods. The Forum is working to minimize sampling variables by implementing a comprehensive monitoring program. It is enlightening, however, to take at least a cursory look at some of the trends that appear in the SWAT data.
 

TRP student Anna Germundson
rinses sample bottle in preparation
for SWAT sampling.

Increasing worldwide attention is being given to nutrients such as phosphorus and nitrogen compounds as urban and agricultural activities contribute ever-increasing loads to the water cycle. Nitrogen deposition from the atmosphere is occurring at an accelerated rate, even in the alpine lakes and streams of Rocky Mountain National Park, while surface runoff and permitted discharges carry fertilizers, manure, and treated wastewater into the tributaries and main stem of the Big Thompson. Nutrients are of special concern when water is held in lakes or reservoirs where increased nutrient loads contribute to accelerated algal growth. Accelerated algae growth can cause a host of problems, including more costly drinking water treatment, fish kills and fetid conditions.

Reina Shainholtz collects a sample for
River Watch on the Little Thompson River.
TRP is a member of Colorado RiverWatch,
and supports other schools and citizen
groups in River Watch Sampling.

Total Organic Carbon (TOC) is a measure of the amount of carbon from organic sources such as leaves and detritus, animal waste, and algae. Historically, this class of compounds has not received much attention in a general sense, but it is of great concern to drinking water providers who use chlorine as a disinfectant during the treatment process. Organic carbon reacts with chlorine to form carcinogenic disinfection by-products (DBP's). Drinking water treatment plants are held to very stringent standards for these DBP's, and must adjust their treatment process to handle high levels of organic carbon.

Bacteria levels serve as an indicator of possible disease causing organisms that are of special concern to water recreationists, hikers, and drinking water providers. Coliform bacteria enter the water from animal wastes and treated wastewater - the same pathway through which giardia, cryptosporidium, and other pathogens arrive.  While most of us are not prone to health risks from coliform infections, high levels of these bacteria can indicate a greater likelihood that disease causing organisms are present. Waters classified for aquatic recreational use in Colorado are protected by water quality standards based on coliform bacteria levels.

Thanks to the dedicated students of the Thompson River Project, we have meaningful baseline data to use in designing and evaluating the Forum's monitoring program. Forum members can use this initial information as we begin reducing and eliminating water quality problems in the Big Thompson Watershed.